Process hazard analysis
A systematic assessment of the potential hazards associated with an industrial process involving highly hazardous chemicals, used to identify and evaluate risks before they cause accidents. A core element of process safety management.
Also known as
By jurisdiction
UK HSE
“hazard study”Close equivalentCOMAH 2015 (SI 2015/483) requires upper-tier establishments to prepare a safety report demonstrating that major accident hazards have been identified and that necessary measures have been taken. The HAZOP (Hazard and Operability Study) and other systematic techniques are equivalent in function to PHA and are used in UK major hazard practice, though COMAH does not prescribe a named methodology.
Irish HSA
“process hazard analysis”Close equivalentThe EC (Control of Major Accident Hazards involving Dangerous Substances) Regulations 2015 (SI 2015/209) require safety reports from upper-tier establishments, which must demonstrate systematic hazard identification and risk analysis. HAZOP and equivalent techniques are used in Irish major hazard practice.
US OSHA
“process hazard analysis”PHAExact equivalentOSHA 29 CFR 1910.119(e) requires employers to perform an initial process hazard analysis on each covered process. The PHA must identify potential causes and consequences of fires, explosions, releases or reactive chemical incidents. Recognised methodologies include what-if, checklist, hazard and operability study (HAZOP), failure mode and effects analysis (FMEA), fault tree analysis, or an appropriate equivalent. PHAs must be updated and revalidated at least every five years.
Practitioner note: Revalidation is required at intervals, not once. An analysis predating significant plant modification is itself evidence of a management of change failure.